Vineyard site selection

The quality of grapes produced in a vineyard will largely determine the success of a winegrowing business, and this in turn will be affected by the quality of the site. Far too often, the purchase of land is driven by factors other than grape quality and this can be expensive in the long run. It is strongly recommended that the winegrowing considerations be factored in early during the decision making process. Before veiwing any properties, it is important that you have a clear understanding of your intentions. If this involves developing a winegrowing business, then you will need a business plan detailing the types and quantities of wine you intend to sell and where, for how much and how you intend to sell it. Is your intention to sell grapes or wine? If you intend to sell wine, will you make it - or will you have the work contracted out? Do you have the resources to make the business successful? The answers to these questions will be invaluable when deciding if winegrowing is for you and in choosing the correct property.

Selecting a site

The climate needs to be appropriate for the vine to grow and mature its fruit and while sites with with too little heat accumulation fail in this instance, sites with too greater heat accumulation produce wines that lack the desired flavour charcteristics. Fortunately, grapevine varieties used in wine, range in their heat requirements, with varieties like Pinot Noir and Reisling having lower heat requirements than varieties like Cabernet Sauvignon and Shiraz. Not only must the site's climate be appropriate for growing grapes, the type of grape grown needs consideration. If you can't produce the quality of grapes you require from the selected variety, the site is wrong.

While it is true that - the greatest wines of any particular variety will come from areas at the extreme limit of that varieties ability to ripen - it is also true that great wines are not produced every vintage. By pushing the limit to where a variety will ripen, you expose a business to the risk, that in many years the fruit will not fully ripen, resulting in mediocre (or worse) wine quality. This is the "art and science" of good site selection and while wine quality, like art, is often subjective, good science goes a long way in maximising a wine's potential, or conversely minimising the potential of producing poor wine.

Key climatic factors

The most important climatic factor is temperature, or more specifically the accumulation of heat over a given growing season. This is known as the growing degree days (GGD's) and is typically measured by summing the daily average temperature over the season. Cool climate grape varieties have GDD's in the order of 700 - 900 units, while warm (hot) climate varieties are up around 2200 - 2500 units. Other key climatic factors include rainfall and humidity, proness to frosting and wind. Sites with low (400 mm) to moderate (1000 mm) rainfall, falling mainly during winter and spring are best, as wetness (humidity), prior to and during ripening will cause fungal diseases and be cooler due to cloud cover. Frosts destroy vine tissue and excess wind inhibits vine growth and delays fruit ripening.

Key soil factors

Vines don't like wet feet...but without water they won't grow

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